So, the only way that I've been able to solve for this is to create a series of Roles, and then set a notification to fire, per each role.
As an example, I have Sales Teams which consist of a Team Lead, a (or many) Sales Reps, and a (or many) Account Managers.
When a notification goes out based on triggered actions in the record, I had to set a notification to go out for each role.
It's cumbersome, and I would hope that a CC option either is, or will become available soon. But for now, this has been my work around.
Hope it helps.
Mike